zynq: Fix typo in Makefile about custom ps7_init file

Trivial fix.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/board/xilinx/zynq/Makefile b/board/xilinx/zynq/Makefile
index 20522fb..fd5d6fe 100644
--- a/board/xilinx/zynq/Makefile
+++ b/board/xilinx/zynq/Makefile
@@ -25,7 +25,7 @@
 ifneq ($(wildcard $(srctree)/$(src)/ps7_init_gpl.c),)
 init-objs := ps7_init_gpl.o
 $(if $(CONFIG_SPL_BUILD),\
-$(warning Put custom ps7_init_gpl.c/h to board/xilinx/zynq/custome_hw_platform/))
+$(warning Put custom ps7_init_gpl.c/h to board/xilinx/zynq/custom_hw_platform/))
 endif
 endif